Angle attachment for dental engines



(No Model.) 4

O. H. DAVIS.

ANGLE ATTAGHM ENT'FOR DENTAL ENGINES. w No. 522,291. Patented July 3,1894-.

PATENT OFFICE ANGLE ATTA E T F'Q' DENTAL ENGINES.

/ f sPnoIrIoATIon forming part r .6aGar gesM5 3 ;ggated July 3,1894.

, Application filed April 18, 1893.

To all-whom, it may concern/.2 A. Y i

Be it known that I, CHARLES H. D VI a citizen'of the United States,residing at Worcester, in the county of Worcester and State ofMassachusetts, have invented a new and useful Improvement in AngleAttachments for Dental Engines, of which thefollowing is aspecification, reference being had to the accompanying drawings, inwhich- Figure 1 is a side View of the attachment shown in central,longitudinal, sectional view, in order to disclosethe'operating parts?Fig. 2 is a central, sectional, longitudinal view of the tubular shellprovided atone end with an internal screw thread and at the opposite endwith a grooved neck,upon which the'headis'; journaled. Fig. 3 is anend'view of the'tubu-f lar shell in Sectional view in Fig. 2.- Fig. is acentral, sec'tionaL-view of the head with the hollow tool carryingQspindle removed." Fig. 5 is a detached view of the screw threadedcollar held by the grooved neck of the tubular shell. Fig. 6 is an endview of the same. Fig. 7 is a detached and side view of the screwthreaded cap by which the opening in the head is closed. Fig. 8 is anendview of the same shown in section on line 8, 8,"Fig. 7, in order todisclose the pivoted latch by which the tool is retained. Fig. 9represents the same view as Fig. 8, but with thepivoted latch disengagedfrom the tool and Fig. 10 is a side view of the attachment showingthehead in the position in which the tool is held with its axis at rightangles with thefaxis of the driving shaft, but as offset, or lying in adifierent plane. 1'

Similar letters refer to similar partsin the difierent figures. I

The object of my invention is to provide an angle attachment for adentalengine, by which a tool may be held and operated, either at an acute, oran obtuse angle to the axis of the hand piece, and at the same time withthe axis of the tool and the axis of the hand piece lying in the samevertical plane, and also by which the tool may be ofisetas representedin Fig. 10, and I accomplish these objects by the means hereinafterdescribed and shown in the accompanying drawings, in which-v A denotes atubular Sleeve, provided at one end with an internal screw thread A, bywhich the sleeve is attached to the section B,

Serial N5. 470,906. (Nomodel-l serving as a handpiece bywhich theinstrument is held by the operator. Extending through these'ction Bisa'rot'ating spindle B, operatively connected in the usual mannerwith'the" flexible shaft of a dental engine and provided at itsinner endwith a cylindrical wheel B preferably filling the interior of thesleeveA, so as to form a bearing at its periphery and provided withthe'beveled gear teeth B The sleeve A is attached at one end to thesection B by the screw thread A and at its opposite end the sleeve A isbent obliquely so the axis of the bent end of the sleeve will form 'anoblique angle preferably of one hun-' =dre'd and thirty-five degreeswith the axis of' fth'e; section B. Upon the bent end of the sleeve A,is 'an'jexternal annular groove forming a neck B ,'adapted to receive ascrew 'threaded collar B, as i epresented'in Figs. 5 and 6,wide enoughtofill the 'neck B and turn freely therein, the collar being preferablycut apart upon one' 'side' as at B in order to allow it to' be expandedandsprung over the flangeBt l Thesleeve A is-provided'with a concentricchamber A to receive the cylindricalwheel B? and also with a cylindricalchamber A concentric with the'b'ot'to'm of the groove B t o 'receive anintermediate cylindrical wheel B and between the chambers A and A and atthe bent portion of the sleeve A is an internal lug 13 having a hole Bconcentric with the chamber A to receive the gudgeon B of theintermediate wheel B The screw threaded collar 13 carries a' head 0provided with an internal screw thread 0 by which the head is screwedupon the collar 13 and at right angles with the axis of the screw thread0, is

a bearing 0 to receive a hollow tool holding v spindle G The head isprovided with a spur O concentric with the screw thread G and surroundedby an annular concentric cham-. .ber C to receive the end of theintermediate wheel B which incloses and turns-upon the spur G The head 0is also provided with a circular chamber 0 concentric with the bearing 0to receive a gear 0 preferably inte-v gral with the hollow spindle O Theintermediate Wheel B is provided with beveledgear teeth 0 which areengagedby the gear teeth 13 and at the opposite end with the beveledgear teeth which engage the teeth of the gear 0 causing the rotarymotion of the spindle B to be imparted to the hollow spindle C The head0 is provided with ascrew thread 0 to receive a screw threaded cap Dprovided with a concentric opening D to receive a tool E and having uponone side a slot D within which is pivoted a plate D provided to with anotch D adapted to inclose an annular groove, or neck E upon the tool Eby which the tool is locked within the hollow spindle C The pivotedlatch plate D is provided with an elastic prong D provided with a smallprojection D arranged to spring into an indentation D upon the side ofthe head 0 and hold the latch plate D from turning upon its pivotal pinD when the tool is engaged and held by the latch.

The convex side of the sleeve A is provided with a longitudinal groove Fto receive a narrow elastic blade spring F having one end held within arecess, or socket provided in the hand piece B and having its free endlying 2 5 within the groove F with the tip F entering one of a series ofnotches F formed in the head 0. The narrow blade spring F is held withinthe groove F and one of the notches F by means of a sliding ring F",which is capable of being moved back into the position indicated by thebroken lines F where the blade F is thinner, thereby allowing the end ofthe spring to be raised out of the notch F and release the head 0, sothe head and collar 5 B may be turned around the neck B from theposition shown in Fig. 1, in which the tool is held at an acute angle,with the axis of the hand piece, to the position indicated by the brokenlines G, Fig. 1, in which the tool is 0 held at an obtuse angle with thehand piece; the gear 0 being rotated around the gear teeth 0 upon 'theintermediate wheel B as the position of the tool is being changed. Inboth these positions, viz., with the tool held 5 at an acute and at anobtuse angle, the axis of the tool and the axis of the hand piece willlie in the same vertical plane, so that a pressure applied to the end ofthe tool will not tend to rotate the hand piece within the hand of theoperator, or to rotate the sleeve A upon the hand piece. If the head 0be locked in position midway between the position shown in Fig. 1 andthat indicated by the broken lines G, Fig. 1, the tool will then be heldwith the 5 plane of its axis at right angles with a vertical planecontaining the axis of the spindle B, as represented in Fig 10; but thetool carried by the head will in that position be o'fiset, that is, itwill be held in a different vertical 6o plane from that of the spindleB.

The screw threaded collar 13 is provided with a notch H which allows thecollar to be dogged, or held from rotating, which is accomplished bysliding the ring F back into the position F and withdrawing the springfrom its socket in the hand piece and removing it from the groove F,which will allow the tip F to be inserted in the groove 11, which ismade deeper for that purpose, thereby holding the screw threaded collar13 so the head 0 may be rotated independently and screwed upon thecollar for the purpose of taking up any lost motion, or for bringing thebeveled teeth of the gears closer together, in order to compensate forwear.

The angle between the axis of the tool and the axis of the spindle B,when held in the position indicated by solid lines in Fig. 1, will beequal to a right angle minus the angle formed by the axes of the twowheels 13 and B and when the tool is held in the position shown at G,Fig. 1, it will form an angle with the hand piece equal to a right angleplus the angle formed by the axes of the wheels B and 13 but in bothcases with the axis of the tool in the same vertical plane as the axisof the hand piece. The number of notches F can, however, be increased inorder to allow the head 0 to be held at different angles from those Ihave described and indicated in the drawings. The attached end of theblade spring F is preferably held by being loosely inserted in a socketprepared for it upon the hand piece, but it can obviously be attached byany other known means, such as screws, which would allow it to beremoved to allow access through the deepened portion of the groove F atH to the notch 11 in the screw threaded collar B When the head 0 isoffset or held in the position with reference to the tubular sleeve A asrepresented in Fig. 10, a pressure applied upon the end of the tool willtend to rotate the sleeve A and unscrew it from the hand piece and Itherefore lock the sleeve A, as well as the head 0 by means of the latchF, which is held by the hand piece B and inserted in the groove F of thesleeve A. The head 0 is closed by a cap D, provided with a centralopening D in alignment with the hollow tool carrying spindle G theopening D forming a bearing for the tool E, which causes any sidestrain, or pressure, upon the tool to be received by the cap instead ofthe hollow spindle.

I am aware that an angle attachment provided with elbows coupledtogether, by which the angle of the tool may be varied is not new, and Ido not claim such broadly.

What I claim as my invention, and desire to secure by Letters Patent,is-

1. In an angle attachment, the combination with a hand piece, of atubular sleeve carried by said hand piece and bent obliquely thereto andprovided with an external annular groove, a screw threaded collar headin said groove and adapted to rotate therein and a head provided with ascrew thread engaging said collar and having a bearing for a toolholding spindle, whereby said head is adapted to 1'0- tate around saidbent sleeve and of adj ustment on said screw threaded collar,substantially as described.

2. In an angle attachment, the combination with a hand piece, of asleeve attached thereto,

said sleeve being bent at anoblique angle to said hand piece, a headadapted to rotate about said sleeve and a drill spindle carried in saidhead, whereby said drill spindle can be placed atan acute or an obtuseangle with said hand piece and in the same vertical plane therewith andmeans by which said head is held from rotation, substantially asdescribed.

3. In an angle attachment, the combination of a hand piece,a*sleeveattached to said hand piece and bent at an oblique angle thereto, arotating driving spindle and a bevel gear attached to said spindle andinclosed in said sleeve, a head adapted to rotate about said sleeve, adrill spindle jonrnaled in said head, a bevel gear attached to saiddrill spindle, and an intermediate cylinder journaled with its axis atan oblique angle to said driving spindle and provided with gear teethengaging the gears on said driving spindle and said drill spindle,substantially as described.

4. In an angle attachment, the combination of a hand piece B, sleeve Aattached to said hand piece and having a groove F, a tool car rying headjournaled upon said sleeve and provided with notches, said sleeve beingbent at an oblique angle to said hand piece, a blade spring attached atone end to said hand piece 30 and adapted to be pressed into said grooveand said notches by a sliding ring anda ring arranged to slide over saidblade spring and crowd it into said groove against the tension of thespring, substantially as described,

5. Thecombination of the sleeve A; provided with an annular groove 13,of a screw threaded collar B capable of turning within said groove andprovided with a notch H to allow the collar to be held from rotation, ahead 0 carried by said screwthreaded collar, a tool spindle journaled insaid head, a driving spindle j ournaled within said sleeve andintermediate gearing by which the rotation of said driving spindle iscommunicated to said tool carrying spindle, substantially as described.p

6. The combinationof the head 0, rotating tool spindle C cap D, providedwith an opening D concentric with the axis of said drill spindle, alatch plate D pivoted upon said cap and having a notch D and an elasticprong bent at right angles to said latch and having a projection Dadapted to engage an indentation in the side of the headO,'substantiallyas described. I

CHARLES 1-1. DAVIS.

Witnesses: v

RUFUS B. FOWLER, EMMA KESTER,

